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Detailed microbiostratigraphy and basin evolution of the Lower Cretaceous deposits in the Rayen area, south of Kerman Region, SE Iran are investigated for the first time in two sections. The section no. 1 is 324.6m in thickness and comprises five lithostratigraphic units. The section no. 2 is 218 m in thickness and includes three lithostratigraphic units. The identified fauna and flora include 41 benthic foraminifera and 11 calcareous algae species. The identified assemblage indicates that the marine strata in both sections were deposited during the Barremian to Albian. The microfacies analyses carried out on 22 carbonate and 2 clastic microfacies indicate that the deposits in the section no. 1 were deposited on a homoclinal carbonate ramp, whereas in the section no. 2 they were deposited on a rimmed carbonate shelf. Generally, the Cretaceous deposit in the two studied sections represent different sedimentary models and fossil content indicating different basin evolution histories. The paleogeographic setting of the studied area on the south eastern margin of the Central- East Iranian Microcontinent and the active tectonic history during the Mesozoic suggest that the syndepositional tectonism influenced the basement’s morphology and resulted in changes in the fossil diversity and sedimentary nature of adjacent sedimentary basins. La microbioestratigrafía detallada y la evolución de la cuenca de los depósitos del Cretácico Inferior en el área de Rayen, al sur de la región de Kerman, sureste de Irán, se investigan por primera vez en dos secciones. La sección núm. 1 tiene 324.6 m de espesor y comprende cinco unidades litoestratigráficas. La sección núm. 2 tiene 218 m de espesor e incluye tres unidades litoestratigráficas. La fauna y flora identificada incluye 41 foraminíferos bentónicos y 11 especies de algas calcáreas. El conjunto identificado indica que los estratos marinos en ambas secciones fueron depositados durante el Barremiense al Albiense. Los análisis de microfacies realizados en 22 microfacies carbonatadas y 2 clásticas indican que los depósitos en la sección no. 1 se depositaron en una rampa de carbonato homoclinal, mientras que en la sección no. 2 se depositaron en una plataforma carbonatada con borde. En general, el depósito del Cretácico en las dos secciones estudiadas representan diferentes modelos sedimentarios y contenido fósil que indican diferentes historias de evolución de la cuenca. El marco paleogeográfico del área estudiada en el margen suroriental del microcontinente iraní centro-oriental y la historia tectónica activa durante el Mesozoico sugieren que el tectonismo sindeposicional influyó en la morfología del basamento y resultó en cambios en la diversidad fósil y la naturaleza sedimentaria de sedimentos adyacentes. cuencas.

This paper presents a new interpretation of the paleogeographic evolution of the northern side of the High Atlas Range of Marrakesh (Morocco) based on a tectonic, lithological, sedimentological, and paleontological description of the three outcropping Upper Cretaceous Formations: The Anou-Nfeg Formation, the Aït Abbes Formation, and the Chichaoua Formation. In biostratigraphical terms, these formations areas signed to the Coniacian, Santonian, and Maastrichtian, respectively, and record three tectonic phases responsible for the geodynamic evolution of this part of the High Atlas Range. These phases are confirmed by the vertical elevation of the earth’s surface and the formation of some small restricted basins. A sedimentary pause corresponding to the Campanian has been recorded. Based on these findings, we conclude that these Formations were deposited in a confined environment influenced by the episodic marine incursions under a hot and humid climate. Este artículo presenta una nueva interpretación sobre la evolución de la estratigrafia secuencial y paleogeografía del flanco norte de la Cordillera del Alto Atlas de Marrakech (Marruecos), basada en una descripción tectónica, litológica, sedimentológica y paleontológica de las tres formaciones aflorantes del Cretácico Superior: la Formación Anou-Nfeg, la Formación Aït Abbes y la Formación Chichaoua. Bioestratigráficamente, estas formaciones se asignan respectivamente al Coniaciano, Santoniano y Maastrichtiano, y son el registro de tres fases tectónicas responsables de la evolución geodinámica de esta parte del Alto Atlas. Estas fases se confirman por un movimiento vertical ascendente de la superficie y la formación de pequeñas cuencas restringidas. La investigación de campo confirma una pausa sedimentaria durante el Campaniano. Sobre la base de estos hallazgos, llegamos a la conclusión de que estas formaciones se depositaron en un entorno confinado influenciado por incursiones marinas temporales en climas cálidos y húmedos.

On the western part of the Valles–San Luis Potosí Platform located in Cerro Quemado near Temazcal, municipality of Armadillo de Los Infante, two sequences crop out. The lower one is the shallow-water El Abra Formation of the mid–upper Cenomanian, unconformably covered by a deep-water deposit of the upper Maastrichtian informally called here the “Temazcal unit.” The succession presents a nonconforming contact between these two sedimentary units, displaying a hiatus as the result of a time of non-deposition in the sedimentary record, showing a subaerial exposure with erosion yielding topographic relief. Based on the lithological changes from the underlying limestone toward the overlying silty limestone, as well as a detailed biostratigraphic study based on foraminiferal associations that provide an accurate dating, it has been possible to estimate the magnitude of the hiatus, which spans from the lower part of the Turonian, including the Coniacian, the Santonian, and possibly the lower part of the Maastrichtian. En la parte occidental de la Plataforma Valles-San Luis Potosí en la localidad cerro Quemado cercano a El Temazcal, municipalidad de Armadillo de Los Infante, afloran dos secuencias: una inferior de aguas someras de la Formación El Abra del Cenomaniano medio-superior y, sobreyaciendo en discordancia, un depósito de aguas profundas del Maastrichtiano superior llamado informalmente “unidad Temazcal”. El contacto discordante entre estas dos unidades sedimentarias mostró un hiatus como resultado de un tiempo de no depósito en el registro sedimentario, combinado con la erosión y que produjo un relieve topográfico. Sobre la base de los cambios litológicos desde la caliza subyacente hacia la caliza limosa, así como del estudio bioestratigráfico detallado basado en las asociaciones foraminiferales, se ha establecido una datación precisa, haciendo posible estimar la magnitud del hiatus, que se extiende desde la parte inferior del Turoniano, incluyendo el Coniaciano, el Santoniano y posiblemente la parte inferior del Maastrichtiano.

[Objective] To investigate the height-diameter relationship in strata (including the whole stand and every stratum) of typical natural broad-leaved forests in mid-subtropics. [Method] The Schumacher (S) model and Curtis (C) model were chosen to fit the height-diameter relationship in strata of all plots based on the data of typical natural broad-leaved forest in mid-subtropics. [Result] The results showed that both the S model and C model could fit the whole stand (R2>0.86) and stratum Ⅲ(R2>0.58) well, and the RMSE and AMR were small. But both the S model and C model could not fit the stratum I and Ⅱ well, the R2 were small, almost stayed and their values were between 0.2 and 0.3. Because of the bigger R2, smaller RMSE and ARM, the C model was selected to compare the height-diameter relations in each stratum, and the bigger AMR would be brought when using the whole stand height-diameter model to estimate the height in each stratum (except the whole stand); although the R2 of the height-diameter model in strat

The Geologic Time Scale 2012, winner of a 2012 PROSE Award Honorable Mention for Best Multi-volume Reference in Science from the Association of American Publishers, is the framework for deciphering the history of our planet Earth. The authors have been at the forefront of chronostratigraphic research and initiatives to create an international geologic time scale for many years, and the charts in this book present the most up-to-date, international standard, as ratified by the International Commission on Stratigraphy and the International Union of Geological Sciences. This 2012 geologic time scale is an enhanced, improved and expanded version of the GTS2004, including chapters on planetary scales, the Cryogenian-Ediacaran periods/systems, a prehistory scale of human development, a survey of sequence stratigraphy, and an extensive compilation of stable-isotope chemostratigraphy. This book is an essential reference for all geoscientists, including researchers, students, and petroleum and mining professionals. The presentation is non-technical and illustrated with numerous colour charts, maps and photographs. The book also includes a detachable wall chart of the complete time scale for use as a handy reference in the office, laboratory or field. The most detailed international geologic time scale available that contextualizes information in one single reference for quick desktop access. Gives insights in the construction, strengths, and limitations of the geological time scale that greatly enhances its function and its utility. Aids understanding by combining with the mathematical and statistical methods to scaled composites of global succession of events. Meets the needs of a range of users at various points in the workflow (researchers extracting linear time from rock records, students recognizing the geologic stage by their content).

This thesis explores the scientific controversy over the 'Anthropocene', a putative new epoch of geological time conceived in 2000 by atmospheric chemist and earth system scientist Paul Crutzen. I trace the conception of the Anthropocene and explore its spread through a range of disciplines from the earth sciences to the humanities. Particular attention is paid to the Anthropocene Working Group (AWG) of the International Commission on Stratigraphy. This group was tasked with considering whether or not the Anthropocene should be subject to stratigraphic formalisation and be made 'real' insofar as the discipline of stratigraphy was concerned. The group's efforts, and the wide-ranging response to them, reveal the challenge of making sense of knowledge as it moves across different disciplines, settings, and contexts. While the AWG was tasked with producing a specifically stratigraphic response to the rising prominence of the Anthropocene, in performing their investigation the group took on board wide-ranging multidisciplinary expertise. As well as raising questions about the appropriate criteria for the group's investigation, the response to the group's efforts from a diverse range of disciplines illustrates the disunity of interdisciplinary work. The movement of the controversy from scholarly journals into an increasingly public sphere reveals further questions about the relationship between scientific authority and society as a whole. While different communities disagreed about the scientific value of the Anthropocene, many shared in their recognition of the role this scientific framing could play in fomenting a political response to anthropogenic global change. This thesis argues that scholarly debates about the Anthropocene illustrate questions about authority, epistemic privilege, and the relationship between disciplines that have ramifications beyond the controversy itself.

This study investigates the interplay of evolving tectonic and submarine sedimentation processes in the northwest Aegean Sea using marine multichannel seismic profiles. We identify an extensive basin developing in the Thermaikos Gulf inner shelf, outer shelf, and slope leading to the 1500 m deep West North Aegean Trough (NAT). We establish the unconformable extent of Eocene and Oligocene sequences on the upper shelf and trace their continuation in the deeper shelf and slope of Thermaikos Gulf. The start of the Miocene and Middle Miocene developed below the well-established Messinian bounding reflectors that are mostly erosional. Important lateral variations are observed within the Messinian sequence, which is up to 0.8 s thick. Messinian prograding clinoforms are identified on the Thermaikos Gulf shelf and southeast of Chalkidiki, and a zone of irregular reflectors is attributed to the Messinian salt layer. The transpressional deformation of the Messinian in the southwestern margin constrains the timing of westward progradation of the North Anatolian Fault during Messinian. The Pliocene-Quaternary sediments are 0.6–1.8 s thick, showing the overwhelming effect of tectonics on sedimentation plus the northwards Quaternary activation at the Thermaikos apron.

Chinese loess has a wide range of distribution, large strata thickness, and high stratigraphic completeness, and has been widely studied by scholars. By consulting and summarizing literatures, this paper generalizes the previous research results, and summarizes the microstructure characteristics of the loess, such as loess skeleton particles, the way they are connected to each other, the pore types, and the regional changes of the loess microstructure. Finally, the prospects of relevant researches on the loess microstructure were prospected.

The Global Boundary Stratotype Sections and Points (GSSPs) for the bases of all seven international Devonian stages have been formally defined and ratified by IUGS till 1996, and nowadays, the main tasks for Devonian stratigraphers include further subdivision of these standard stages, strictly constrained absolute ages for the boundaries, and precise neritic-pelagic and marine-terrestrial correlations using multidisciplinary stratigraphy methods. Establishment of high-resolution Devonian integrative stratigraphy framework and timescale of China would play an important role in improving regional and international correlation, facilitating the recognition of important stratigraphic levels in different paleogeographic settings, and understanding the evolution pattern of biota, paleoclimate and paleoenvironment during this critical interval. Based on well-studied bio- and chronostratigraphy of Devonian in South China and adjacent areas, in combination with recent achievements in carbon isotope stratigraphy, event stratigraphy and radioactive isotope ages, this paper briefly summarize the research history and current status of Devonian chronostratigraphy of China, and for the first time introduce Devonian integrative stratigraphy framework of China. Up to date, few studies have been conducted on the astronomical cyclostratigraphy and high-resolution radioactive isotope dating in Devonian of China, which should be our main focuses in the near future.